Pencil sharpening device



-July 10, 1934. M, H, STEINKE 1,965,610

PENCIL SHARPENING DEVICE Filed Oct. 9, 1931 Flc? wl.

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INVENTOR Mu/M Patented `luly 10, 1934 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates to pencil sharpening devices and particularly to the type of device adapted to serve draftsmen and stenographers. Usually a draftsman or other artisan requires a rela- 5 tively long and fine point on a pencil to execute drawings or Iine writings. In order to secure such a point on a pencil the knife on this Sharpener is only required to cut the wood and not the lead of the pencil. Heretofore, Sharpeners were unsatisfactory for the reason that often when the lead was not concentric in the wood, as it is very often the case, the knife blade produced on one side a saw cut in the lead which greatly weakened the lead so that it easily broke when the pencil was withdrawn, or required considerable time and patience in order to secure a good workable point. Furthermore, sharpening of the long lead point was obtained by friction on a piece of sand or ernery paper. This resulted in sharp- 20 ening the lead to a fine pin point which, however,

often pierced the drawing paper or easily fractured the brittle lead when used, because the very last end had a rock-like structure due to the relatively rough grain of the abrasive.

An object of this invention is to overcome these disadvantages by an eflicient and inexpensive device in which the long lead point is strong and smooth and the extreme of the lead is incapable of piercing the drawing.

In accordance with oney aspect of this invention the sharpening device comprises a casing which may be easily mounted on the front of a drawer of a table or held in the hand, including a dish shaped circular member or base having a central aperture through which extends a tubular pencil holder.

According to this invention a sharpening device is provided in which the cutting edge is annular or cylindrical to secure concave cutting of the pencil wood either in the direction of the longitudinal axis of the pencil or at an inclined angle thereto. This arrangement also insures a continuous renewable cutting edge for long service. The device comprises a hollow receptacle having a central pencil holder and an exterior dish shaped portion for sharpening the lead of the pencil. The cylindrical cutter is mounted in a groove of the receptacle with an edge entering the tubular pencil holder. The Wood cutting portion of the cylindrical cutter may also be mounted transverse to the dish-shaped lead sharpening portion is accordance with another aspect of this invention. When the sharpening of the pencil is accomplished in a closed receptacle an audible indicating means may be (Cl. 1Z0-93) provided to signify when the point is secured.

These and other features of the invention will be more clearly understood from the following detailed description in connection with the accompanying drawing in which;

Fig. 1 is a top plan view of a pencil sharpening device employing the cylindrical cutter of this invention showing the position of the cutter in the assembly,

Fig. 2 illustrates in shown in Fig. l taken figure,

Fig. 3 illustrates the relationship of a pencil sharpened with a cylindrical cutter in accordance with this invention,

Fig. 4 is an enlarged fragmentary View showing the position of the cutter and the pencil,

Fig. 5 is an enlarged view of a modified form of audible signal shown in Fig. 2,

Fig. 6 shows schematically the position of the cutter member with respect to the longitudinal axis of the pencil,

Fig. 6a is a composite schematic View similar to Fig. 6 showing the cutter member oiTset with re- 80 spect to the longitudinal axis of the pencil and inclined at an angle with respect thereto,

Fig. 7 is a plan view of a modification of the device shown in Figs. 1 and 2 in which the wood cutting portion is arranged transverse to the lead sharpening portion of the device,

Fig. 8 shows in cross-section the device of Fig. 7 on the line 8 8.

In accordance with this invention the pencil may be sharpened with a device in which an annular or cylindrical cutter is employed. It will be noticed that the cutter imparts a concave cut to the wood of the pencil to furnish a long lead point. Furthermore, the arc of the cutter in engagement with the wood clears the length of lead so that saw cuts or nicks are not present to weaken the lead. One method of mounting the cylindrical cutter is shown in Fig. 6 in which the cutting edge 30 is directly in the plane of the 100 longitudinal axis of the pencil. In this position the cutting direction is perpendicular to the longitudinal axis of the pencil. A shaving eiect, or in other words, a tangential cutting direction may be obtained by osetting the cutter 28 as 105 shown in full line in Fig. 6a in Which the cutting angle 31 is a tangent with respect to the axis of the pencil and the plane of the cutter edge 30. The same effect may be obtained by placing the cutter on the longitudinal axis of the pencil 11,0

desired length of 65 cross-section the device on the line 2-2 of that but inclined at an angle as shown in dotted outline 32 in Fig. 6a.

Since the handling of the cylindrical cutter would be extremely awkward it is desirable to arrange the cutter in a mounting as shown in Figs. l and 2. This mounting comprises an open ended cup receptacle 33 formed with a central pencil holder 34 which terminates in a sleeve portion 35 in which the pencil is inserted. A circular rim 36 on the receptacle, coextensive with the sleeve 35, forms a base for an abrasive strip 20 while the annular surface 37 may be smooth or polished.

The cutter 28 is inserted through the open end of the receptacle 33 into a curved radial slot or groove 38 and is held therein by the spring nger or clip 39 on a back plate 40 which is fastened to the table or desk by a screw 4l. The receptacle may be attached or locked on the back plate by pins 42. The cavity 43 in the receptacle holds the wood shavings from repeated pencil sharpening operations.

Since the sharpening of a pencil in this type of receptacle is concealed from view an audible signal means is provided, such as a clicking device 51 in the form of a resilient metallic strip having a conv x indent-ation 52. The strip 5l is fastened at one end to the plate 4G and adjustable by screw 53.

In Fig. 4 the cutting edge 30 which is stationary in the mounting removes the wood shavings from the pencil when the pencil is rotated. in a clockwise direction. it is apparent that when one portion of the cutter is dull the cutter may be easily rotated a few degrees tc present a new cutting edge and therefore represents both economy and eiiciency in the use of this device.

Figs. '7 and 8 show a modiiication of the sharpening device embodying the cylindrical cutter member of this invention in which the wood cutting portion is arranged transverse to the lead sharpening portion. In this arrangement a cupshaped member 44 having a polished disc surface is provided with the abrasive lining 2() similar to Fig. l. A pencil holder is positioned on the rear of the member 44 and comprises a tubular pencil cavity 45 having a loop cutter holder 46 formed near the pencil point end of the cavity. The cutter holder is coaxial with member 44,

with the pencil cavity 45 offset with respect to the axis of the member 45 and the holder 46. The pencil holder may be formed integral with the member 44 or otherwise secured thereto if not made integral. The holder 46 forms a seat for a cylindrical cutter 28 which has a portion 47 entering the pencil cavity to cut the wood from the pencil in the saine manner as explained in connection with Figs. l and 2.

It is, of course, understood that while several modications have been disclosed which embody the features of this invention, it is apparent that changes in construction may be made without departing from the scope of the invention as defined in the appended claims:

What is claimed is,

l. A pencil sharpening device comprising an open ended receptacle having a central tubular portion provided with a slot and an internal radial curved groove extending from said slot, a cylindrical cutter within said groove and extending into said slot, and a retaining cover member on said receptacle engaging said cutter member.

2. A pencil sharpening device comprising a closed receptacle having an aperture for the reception of a pencil, a knife blade mounted in said receptacle for cutting the wcod from said pencil without engaging t e lead thereof, and audible signaling means adapted to be engaged by the end of the pencil to indicate the length oi the lead point desired.

3. A pencil sharpening device comprising a closed receptacle having a central tubular aperture adapted to receive a pencil, a knife blade for sharpening said pencil, and a resilient clicling member supported within said receptacle and adapted to ce actuated by the point of the pencil to give an audible signal.

4. A pencil sharpening device comprising a receptacle having a pencil receiving holder, a cylindrical cutter adjacent said holder, the surface of said cutter being parallel to the axis thereof and having an arcuate edge adapted to exert a sidewise cutting force on the pencil substantially parallel to the axis of the pencil holder, and means holding said cutter within said receptacle.

MAX H. STEINKE. 

